The invention relates to a clamping element with two clamping jaws guided in parallel for clamping pieces in a flexible position, especially for supporting the workpieces in their preset clamped position at any desired point.
Clamping elements that fix the workpiece in a positioned manner used to clamp workpieces. Labile and longer workpieces required additional clamping units, by means of which the are supported at all critical points in a defined manner. These clamping elements must be brought into contact with the workpiece after the latter has already been fixed in its position. Such clamping units must be approached such that the workpiece will not be twisted or deformed at the points at which the clamping units come into contact with it. Thus, high requirements are imposed on such clamping elements.
Clamping elements are usually actuated hydraulically. The hydraulic pressure is introduced such that the clamping element moves its clamping jaws toward each other or away from each other. Discrepancies in the hydraulic system or in the friction surfaces, which affect the moving parts, may easily lead to twisting of the workpieces.
The prior-art clamping elements do not meet these requirements in all cases. Special solutions, i.e., units adapted to the particular application, are preferred in most cases; prospectus of Rxc3x6mheld Spannsysteme H 4.307, 9-95 edition. This leads to a large number of components.
The object of the present invention is therefore to design a clamping element such that it can be used universally, adapts itself automatically to all conditions and, moreover, maintains its clamped position regardless of external effects, e.g., a pressure drop in the line. In addition, labile points shall be stabilized on greatly different workpieces with one element.
Thus, the present invention is based on a clamping element with two flexibly movable slides arranged in parallel, on which the clamping jaws are attached. During the clamping operations, the clamping jaws come into contact with the workpiece in a flexible position in a tong-like manner. Thus, two equal contact forces directed in opposite directions act on the workpiece at two opposite points. The actions of these two contact forces are mutually abolished according to the principle of action equals reaction and thus do no lead to deformations or twisting of the workpiece.
According to the invention, a clamping element is provided for clamping workpieces, which are already mounted in their positioned position. A supporting mount is necessary at any desired point and is provided by clamping jaws which can be moved to the workpiece and can be fixed. Two slides are guided in parallel and are slidingly guided in guide paths which are provided in cutouts of a housing. The force for moving the slides is introduced by plunger pistons which act on the front sides of the slides and thus form a short lever arm between the introduction of force and the action of the force.
The plunger pistons may be arranged in the piston plates of the housing and pressure may be admitted to them via the same hydraulic connection. The slides of the clamping element may be equipped with replaceable and attachable clamping jaws. A piston acting at right angles to the plane of the slides may be introduced into the housing under the slides. The slides may be provided with a recess which extends in a wedge-shaped manner. The piston acting at right angles to the plane of the slides may be provided at its head with a wedge, which is guided slidingly in the recess of the slides. In the clamped state, the slides may be fixed with their clamping jaws in contact with the workpiece by pressure being admitted to the piston, by the piston being pulled downward into the housing, thus pulling the wedge at its head into the recess, spreading the wedge and pressing the slides into the guide surfaces of the cutouts. The wedge may be designed such that the slides are fixed in a self-locking manner after the clamping. The slides with their clamping jaws may be moved to the workpiece with a force acting on them uniformly and cause a force that is uniform on both sides to act on the workpiece, which force fixes the workpiece in its position in an unchanged manner.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.